Compound wrench

ABSTRACT

A compound, force multiplying wrench having a head and an arm attached thereto and pivotally connected by an intermediate link to a handle, and a bar pivotally interconnecting the arm and handle on opposite sides of the link, the distance of the arm between the pivot point for the bar and the link being greater than the distance between the pivot point for the bar and the pivot point for the handle. The linkage provides a force multiplying relationship which can be operated in a limited space to either tighten or loosen nuts and bolts. The head may be of any one of a number of types, such as an adjustable monkey wrench type or a ratchet with or without an adapter for a socket wrench.

United States Patent 1191 Richards Oct. 8, 1974 COMPOUND WRENCH Primary Examiner-James L. Jones, Jr. 76 Inventor: Oran 1). Richards, l1l6 /2 Mom, & Green Middleburg St., Elkhart, Ind. 46514 22 Filed: Feb. 1, 1973 [571 ABSTRACT [21] Appt NOJ 328,735 A compound, force multiplying wrench having a head and an arm attached thereto and p1votally connected by an intermediate link to a handle, and a bar pivot- U.S-

R, interconnecting the arm and handle on oppgsite Ill. ides of the link the distance of the arm between the Fleld of Search pivot point for the and the being greater than 81/1779, 177 PP the distance between the pivot point for the bar and the pivot point for the handle. The linkage provides a [56] References cued force multiplying relationship which can be operated UNITED STATES PATENTS in a limited space to either tighten. or loosen nuts and 805,328 11/1905 Tacchi et al. 8l/53 R bolts- The head may be of any one Of a number of 912.507 2/1909 Tacchi 81 /177.9 yp h as an dj stable monkey rench type or a FOREIGN PATENTS OR APPLICATIONS 33:22:; w1th or without an adapter for a socket 486,757 11/1929 Germany 81/53 R 7 Claims, 9 Drawing Figures PATENTEDBBT 81914 9.999.929

SHEET 20! 2 COMPOUND WRENCH In the operation of tightening and loosening nuts and bolts, especially those of a relatively large size, it is frequently necessary to use a large, heavy, and difficult to handle wrench in order to obtain the required mechanical advantage to turn the nut or bolt. These large wrenches are also sometimes difficult to use, in that a large angular movement of the handle is required in order to obtain the mechanical advantage for the initial loosening or final tightening of the nut or bolt. The large size wrenches are frequently difficult to use in close quarters and areas of limited space, and in inconvehient to reach places, and are difficult to use in performing the turning movements rapidly. It is therefore one of the principal objects of the present invention to provide a compound wrench which provides a substantial increase in mechanical advantage without a corresponding increase in size, and which can provide a mechanical advantage which cannot for practical design and operational reasons be obtained with the conventional wrench.

Another object of the invention is to provide a force multiplying wrench which will provide a high ratio of mechanical advantage to length of handle, and which can be used for turning nuts requiring substantial force to perform the operation using repeated movements of the wrench handle, and for those requiring only a small force, using a rapid sweeping movement of the handle for fast removal or tightening of the nut or bolt.

A further object of the invention is to provide a compound wrench which is simple in construction and operation and which is versatile and capable of being used with a variety of different types of heads.

Additional objects and advantages of the invention will become apparent from the following description and accompanying drawings, wherein:

FIG. 1 is a perspective view illustrating the manner in which the present compound force multiplying wrench is used;

FIG. 2 is an elevational view of one side of the wrench indicating the manner in which it operates to rotate a nut or bolt in the clockwise direction as viewed in the figure;

FIG. 3 is an edge or side elevational view of the wrench;

FIG. 4 is an elevational view of the side opposite that shown in FIG. 2, illustrating the manner in which the wrench is operated to rotate a nut or bolt in the counterclockwise direction;

FIG. 5 is a perspective view of the wrench illustrating a different type of head;

FIGS. 6 and 7 are fragmentary perspective views of the head of the wrench and a portion of the connecting lever illustrating the manner in which the wrench can be used to operate socket wrench heads; and

FIGS. 8 and 9 are perspective views of the wrench illustrating further types of heads which may be used satisfactorily in combination with the compound wrench.

Referring more specifically to the drawings, numeral 10 indicates a wrench embodying the present invention consisting generally of a head 12, operating lever 14 and handle 16. Various types of heads may be used in place of the type shown in FIGS. 1 through 4, such as the ratchet head 18 shown in FIG. 5 with or without the studs or inserts 20 shown in FIGS. 6 and 7 for receiving various size socket wrenches, or such as adjustable heads of monkey wrench types 24 and 26 illustrated in FIGS. 8 and 9. The principle of the force multiplying lever arrangement with each of the various heads illus trated is essentially the same in each instance.

Lever 14 includes an arm 30 rigidly attached to the head and connected to handle 16 by link 32 pivotally connected to the lower end of arm 30 by a rivet or pin 34 and to the upper end of handle 16 by a rivet or pin 36. A bar 40 pivotally interconnects arm 30 near head 12 with the inner or upper end of handle 16, the head end of the bar being pivotally connected to the upper end of arm 30 near the head by a rivet or pin 42 and to the handle by rivet or pin 44. While the pivoting elements for connecting the arm, handle and bar are referred to as rivets or pins, other types of connectors such as bolts or studs may be use-d if suitable.

With lever 14 being assembled in the manner shown, movement of handle 16 about the pivot indicated by numeral 44 causes link 32 to pivot arm 30 and head 12 about the pivot indicated by numeral 42. The bar acts as a restraining means so that the force generated at the short end of handle 16 is applied to the long end of arm 30, thus creating the required force at head 12 for rotating a nut or bolt. The are traversed by handle 16 is many times greater than the arc traversed byhead 12, thus substantially multiplying the force without any appreciable overall movement of lever 14.

The leverage advantage gained by the fact that the distance from leverage point 50 of the handle to pivot point 44 is greater than the distance from pivot point 44 to resistance pivot point 36, is increased further by the fact that the distance from leverage point 34 to pivot point 42 is greater than the distance from pivot point 42 to resistance point 52. The design of the wrench creates two separate mechanical advantages, one being at leverage point 50 and the other at leverage point 34. Analysis of the rule governing the mechanical advantage of the lever principle reveals that these two mechanical advantages are not simply added together in the design of this wrench, the two lever advantages rather being multiplied together. For example, in the operation and use of the wrench, if the distance from leverage point 50 to pivot point 44 is four times longer than the distance from pivot point 44 to resistance point 36, then the pressure applied to the handle will be increased four times when this pressure is transferred through the link to the wrench handle at leverage point 34. This increased pressure will again be increased by four times if the distance from leverage point 34 to pivot point 42 is four times longer than the distance from pivot point 42 to resistance point 52. The result will be a sixteen-to-one ratio increase in the pressure over that applied by the user of the wrench.

As a further example of the operation of the wrench, if forty pounds of pressure are applied by the user of the wrench at leverage point 50, the result will be pounds of pressure at resistance point 36. This 160 pounds of pressure will push against leverage point 34 and be increased by four times at resistance point 52. The result will be a torque of 640 pounds of pressure against the nut or bolt. The actual mechanical advantage can be varied by the manufacturer if he wishes to change the distances between leverage points, pivot points, and resistance points.

It is seen from the foregoing that the present invention embodies a compound wrench having a substantial mechanical advantage and yet being compact and easily handled and operated. Variations may be made in the proportions of the arm, link and handle to one another, as well as variations in the size of the wrench, to adapt the wrench to various type operations. The wrench can be adapted to a multitude of uses, and in view of the high torque capable of being generated with little movement of lever 14 by merely using the leverage of handle 50, the wrench can effectively and conveniently be used in places where the conventional wrenches would be unsuited or incapable of performing the operation.

While only one embodiment of the present wrench has been described in detail herein, various changes and modifications may be made without departing from the scope of the invention.

I claim:

1. A compound, force multiplying wrench comprising a head for engaging a nut or bolt, an arm rigidly connected at one end to said head and extending radially outwardly therefrom, a handle, a link pivotally connected at one end to the end of said arm opposite said head and pivotally connected at the other end to one end of said handle, and a bar pivotally connected at one end to said arm adjacent to said head and pivotally connected at the other end to said handle and extending generally in the same direction as said arm and toward said handle, the pivot points on said arm, link and handle being on their respective longitudinal axis, the pivot point between said arm and bar being closer to the head than to the pivot point between said arm and link, the pivot point between said handle and bar being closer to the pivot point between said handle and link than the distance between the pivot point between said bar and the free end of said handle, and the space between said pivot points on said arm being greater than the space between the pivot points on said handle.

2. A compound, force multiplying wrench as defined in claim 1 in which said link and bar are positioned in an overlapping relationship to one another such that the lever which they comprise is in a generally straight line.

3. A compound, force multiplying wrench as defined in claim 1 in which the pivot point between said bar and arm is in close proximity to the head on said arm.

4. A compound, force multiplying wrench as defined in claim 1 in which the distance between the pivot points on the handle for said bar and link is substantially less than the length of handle on the opposite side of the pivot point between said bar and handle.

5. A compound, force multiplying wrench as defined in claim 1 in which said head is of the ratchet type.

6. A compound, force multiplying wrench as defined in claim 1 in which said head is of the ratchet type and is provided with a stud for mounting a socket wrench.

7. A compound, force multiplying wrench as defined in claim 1 in which said head is of the adjustable monkey wrench type. 

1. A compound, force multiplying wrench comprising a head for engaging a nut or bolt, an arm rigidly connected at one end to said head and extending radially outwardly therefrom, a handle, a link pivotally connected at one end to the end of said arm opposite said head and pivotally connected at the other end to one end of said handle, and a bar pivotally connected at one end to said arm adjacent to said head and pivotally connected at the other end to said handle and extending generally in the same direction as said arm and toward said handle, the pivot points on said arm, link and handle being on their respective longitudinal axis, the pivot point between said arm and bar being closer to the head than to the pivot point between said arm and link, the pivot point between said handle and bar being closer to the pivot point between said handle and link than the distance between the pivot point between said bar and the free end of said handle, and the space between said pivot points on said arm being greater than the space between the pivot points on said handle.
 2. A compound, force multiplying wrench as defined in claim 1 in which said link and bar are positioned in an overlapping relationship to one another such that the lever which they comprise is in a generally straight line.
 3. A compound, force multiplying wrench as defined in claim 1 in which the pivot point between said bar and arm is in close proximity to the head on said arm.
 4. A compound, force multiplying wrench as defined in claim 1 in which the distance between the pivot points on the handle for said bar and link is substantially less than the length of handle on the opposite side of the pivot point between said bar and handle.
 5. A compound, force multiplying wrench as defined in claim 1 in which said head is of the ratchet type.
 6. A compound, force multiplying wrench as defined in claim 1 in which said head is of the ratchet type and is provided with a stud for mounting a socket wrench.
 7. A compound, force multiplying wrench as defined in claim 1 in which said head is of the adjustable monkey wrench type. 